linux-toradex.git/kernel/kthread.c, branch Colibri_T30_LinuxImageV2.3Beta3_20141031

kthread: disable preemption during complete()

2012-07-31T21:58:16+00:00

After a kthread is created it signals the requester using complete()
and enters TASK_UNINTERRUPTIBLE. However, since complete() wakes up
the requesting thread this can cause a preemption. The preemption will
not remove the task from the runqueue (for that schedule() has to be
invoked directly).

This is a problem if directly after kthread creation you try to do a
kthread_bind(), which will block in HZ steps until the thread is off
the runqueue.

This patch disables preemption during complete(), since we call
schedule() directly afterwards, so it will correctly enter
TASK_UNINTERRUPTIBLE. This speeds up kthread creation/binding during
cpu hotplug significantly.

Change-Id: I856ddd4e01ebdb198ba90f343b4a0c5933fd2b23
Signed-off-by: Peter Boonstoppel

cpuset: Fix cpuset_cpus_allowed_fallback(), don't update tsk->rt.nr_cpus_allowed

2011-05-28T15:02:57+00:00

The rule is, we have to update tsk->rt.nr_cpus_allowed if we change
tsk->cpus_allowed. Otherwise RT scheduler may confuse.

Signed-off-by: KOSAKI Motohiro 
Cc: Oleg Nesterov 
Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/r/4DD4B3FA.5060901@jp.fujitsu.com
Signed-off-by: Ingo Molnar

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

kthread: NUMA aware kthread_create_on_node()

2011-03-23T00:44:01+00:00

All kthreads being created from a single helper task, they all use memory
from a single node for their kernel stack and task struct.

This patch suite creates kthread_create_on_node(), adding a 'cpu' parameter
to parameters already used by kthread_create().

This parameter serves in allocating memory for the new kthread on its
memory node if possible.

Signed-off-by: Eric Dumazet 
Acked-by: David S. Miller 
Reviewed-by: Andi Kleen 
Acked-by: Rusty Russell 
Cc: Tejun Heo 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: David Howells 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

sched: Constify function scope static struct sched_param usage

2011-01-07T14:55:45+00:00

Function-scope statics are discouraged because they are
easily overlooked and can cause subtle bugs/races due to
their global (non-SMP safe) nature.

Linus noticed that we did this for sched_param - at minimum
make the const.

Suggested-by: Linus Torvalds 
Signed-off-by: Peter Zijlstra 
LKML-Reference: Message-ID: 
Signed-off-by: Ingo Molnar

Merge commit 'v2.6.37' into sched/core

2011-01-05T13:14:46+00:00

Merge reason: Merge the final .37 tree.

Signed-off-by: Ingo Molnar

kthread_work: make lockdep happy

2010-12-22T09:27:53+00:00

spinlock in kthread_worker and wait_queue_head in kthread_work both
should be lockdep sensible, so change the interface to make it
suiltable for CONFIG_LOCKDEP.

tj: comment update

Reported-by: Nicolas 
Signed-off-by: Yong Zhang 
Signed-off-by: Andy Walls 
Tested-by: Andy Walls 
Cc: Tejun Heo 
Cc: Andrew Morton 
Signed-off-by: Tejun Heo

sched: Make sched_param argument static in sched_setscheduler() callers

2010-10-23T15:56:48+00:00

Andrew Morton pointed out almost all sched_setscheduler() callers are
using fixed parameters and can be converted to static.  It reduces runtime
memory use a little.

Signed-off-by: KOSAKI Motohiro 
Reported-by: Andrew Morton 
Acked-by: James Morris 
Cc: Ingo Molnar 
Cc: Steven Rostedt 
Signed-off-by: Andrew Morton 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

kthread: implement kthread_data()

2010-06-29T08:07:09+00:00

Implement kthread_data() which takes @task pointing to a kthread and
returns @data specified when creating the kthread.  The caller is
responsible for ensuring the validity of @task when calling this
function.

Signed-off-by: Tejun Heo

kthread: implement kthread_worker

2010-06-29T08:07:09+00:00

Implement simple work processor for kthread.  This is to ease using
kthread.  Single thread workqueue used to be used for things like this
but workqueue won't guarantee fixed kthread association anymore to
enable worker sharing.

This can be used in cases where specific kthread association is
necessary, for example, when it should have RT priority or be assigned
to certain cgroup.

Signed-off-by: Tejun Heo 
Cc: Andrew Morton